Biological Bases of Behavior

Neurons

There are about 100 billion of this in the human brain. Contains the Nucleus, Cytoplasm, and Cell Membrane. These are unique because of their shape and how they function

Dendrites

They carry information to the cell body from other neurons

Cell Body

Also known as Soma, contains nucleus

Axon

carries information to the next cell

Myelin Sheath

insulates the axon and speeds up the neural impulse

Sensory Neurons, Motor Neurons, Interneurons

Types of Neurons

Sensory Neurons

This type of neuron carries information from sensory systems to the brain. Also referred to as Afferent

Motor Neurons

This type of neuron carries information from the brain to muscles and glands. Also referred to as Efferent

Interneurons

This type of neuron carries information between other neurons

Glial Cells

These are cells that insulate and support neurons. These cells also create the myelin sheath. They remove waste products, provide nourishment, and prevent harmful substances from entering the brain.

Ions

Are charged molecules

Resting Potential

This occurs when more negative ions are inside the neuron than outside. Charge is approximately -70 mV. When in process, the neurons are not transmitting information.

Polarization

When the electrical charge of a cell moves away from zero

Depolarization

When the electrical charge of a cell moves toward zero

Action Potential

This occurs when there is a sudden, massive change in the neuron, and when depolarization reaches the threshold of excitation. Ions flow across cell membrane.

Graded Potentials